1. Field of the Invention
The present invention relates to a substrate transporting device for transporting a substrate such as a semiconductor wafer, a glass substrate for photomask, a glass substrate for liquid crystal display, an optical disk substrate, and the like (hereinafter, simply referred to as a “substrate”), a substrate treating apparatus provided with the substrate transporting device for treating the substrate, and a substrate transporting method for transporting the substrate.
2. Description of the Related Art
Japanese Unexamined Patent Publication No. 2001-93827A discloses a plurality of transporting devices, a fan filter unit, an exhaust fan, and a controller. The transporting devices are each movable vertically. The fan filter unit is disposed above the transporting devices. The exhaust fan is disposed below the transporting devices. The controller controls the exhaust fan. When the transporting devices are moved downward simultaneously, turbulent airflow is generated. At this time, the controller performs control to increase an exhaust amount of the exhaust fan for enhancing downflow of clean air. The enhanced downflow absorbs the turbulent airflow. This prevents particles from entering into treatment units.
Japanese Unexamined Patent Publication No. 2009-076805A discloses a transport chamber, a transport mechanism, a gas supply fan, a gas supply valve, an exhaust fan, an exhaust valve, and a controller. The transport mechanism is disposed in the transport chamber so as to be movable vertically. The gas supply fan and the gas supply valve each supply gas to the transport chamber. The exhaust fan and the exhaust valve each exhaust gas from the transport chamber. The controller controls the gas supply fan, the gas supply valve, the exhaust fan and exhaust valve for adjusting a speed of downflow in the transport chamber. When the transport mechanism moves the substrate downward, the controller performs control such that a rate of downflow is higher than a speed at which the substrate is moved downward. Since the downflow is faster than the speed at which the substrate is moved downward, the downflow is supplied to a surface of the downward-moving substrate. Accordingly, this prevents particles from adhering to the surface of the substrate.
However, the example of the currently-used apparatus with such constructions has the following drawback. That is, even the currently-used example may achieve insufficient suppression of floating particles.